'Sophie'

The unveiling back in early December of the world's most complete Stegosaurus skeleton at London's Natural History Museum won't have escaped many folks within the palaeo community. Naturally, as the UK contingent of LITC and being within easy distance of the museum, Marc and I were duty-bound to make our own visit to the new treasure, even if we were over a month late (where were our invitations to the official do, pray?).

With over 90% of the original specimen present, 'Sophie' is a permanent addition of which the NHM can be justly proud. Rather than being secreted in the now problematic Dinosaur Gallery -- about which much has been written here and elsewhere -- she is instead given prime position of her own in the Earth Hall, near the museum's Exhibition Road entrance, paralleling that of 'Dippy' the Diplodocus in the central Hintze Hall. Mounted in a dynamic, defensive stance, she occupies a rather swanky platform of serried steps, somewhat reminiscent of the atrium of New York's Guggenheim museum.

This individual was reportedly only a young adult when it died, as suggested by 'some features of the hips', according to the signage. The specimen is also perhaps notable for having nineteen back plates rather than the commonly recognised seventeen. The skull here is a cast, though information on the NHM website seems to suggest that fragments of the original did survive.*

Obligatory photographic evidence of the intrepid goons' actual visit, taken by Nicole Heins -- who once contributed her own guest post!

Our readers will have doubtless seen Bob Nicholls' stunning painting commissioned by the museum as part of the exhibit. From the sublime, therefore, you will now be treated to the ridiculous: this doodle I drew on a Moleskine leaflet a while ago in an unoccupied moment (Marc said to include it in the post, 'fo sho', so there it is).

 

*I've since been informed by a friend who works at the NHM that the museum does indeed have the complete skull, and that the one on the mount is a 3D print of it!

Fruitadens: The Little Ornithischian that Could

Another swell piece of research published recently in PLoS One - the official favoritest journal of Love in the Time of Chasmosaurs - is a detailed description of the anatomy and phylogeny of Fruitadens haagororum, the little heterodontosaurid from the Morrison Formation of Colorado, a formation dating to 150 million years ago. It debuted with a brief paper during the infancy of this blog in 2009, but now it's been properly studied, so what's the scoop?

Lead author Richard Butler describes this paper as "the result of a nearly 30 year long project," building on a substantial body of work by coauthor Peter Galton. Heterodontosaurids were bipedal ornithischians, notable for their varied dentition. Many have pronounced fangs, or caniniforms, in addition to leaf-shaped teeth which would have been good for munching vegetation. And one of them, Tianyulong, was preserved well enough to reveal that it bore long, hollow quill-like filaments along its back.

Fruitadens restored by Nobu Tamura, featuring quills like those of Tianyulong.

Understanding the evolutionary trends of these primitive ornithischians is important for what it can reveal about the common ancestor of all dinosaurs. Unfortunately, there are few windows into heterodontosaurid evolution, with the most productive strata dating to the early Jurassic of South Africa, when Heterodontosaurus, Abrictosaurus, and Lycorhinus lived. The Middle Jurassic of Europe has offered a plethora of teeth which hint at substantial populations of heterodontosaurids, but so far has not coughed up any significant remains to help fill in the details of the heterodontosaurid story. But what we have is enough to build a rough sketch of how the clade evolved over the 55 million year stretch that it existed.

Fruitadens was likely an omnivore, eating what plants, insects, and other invertebrates it could find. Like closely related Tianyulong, it was smaller and less specialized for herbivory than the earlier Heterodontosaurus, which was made to process tough plant material. Butler notes that "it appears that Late Jurassic-Early Cretaceous heterodontosaurids were smaller than most Early Jurassic members of the clade, and displayed less sophisticated skull and dental morphologies." They were becoming generalists. As the clade spread across Pangaea, which was fragmenting by the Late Jurassic, evolutionary pressures - perhaps competition from the sauropodomorphs - were pushing the heterodontosaurids into a more opportunistic lifestyle. Sort of a dinosaurian version of a raccoon, scratching out a living any way they could.

More:
Andy Farke's take on PLoS Blogs
A note from lead author Richard Butler
Brian Switek at Dinosaur Tracking